import * as XLSX from 'xlsx'
import * as xlsxStyle from 'xlsx-style'

export function sheet2blob (sheet, sheetName) {
  const wb = XLSX.utils.book_new()
  wb.SheetNames.push(sheetName)
  wb.Sheets[sheetName] = sheet
  var wbout = xlsxStyle.write(wb, { bookType: '', bookSST: false, type: 'binary' })
  var blob = new Blob([s2ab(wbout)], { type: '' }, sheetName)
  // 字符串转ArrayBuffer
  function s2ab (s) {
    var buf = new ArrayBuffer(s.length)
    var view = new Uint8Array(buf)
    for (var i = 0; i !== s.length; ++i) view[i] = s.charCodeAt(i) & 0xff
    return buf
  }
  return blob
}
// 导出excel辅助函数
export function openDownload (url, saveName) {
  if (typeof url === 'object' && url instanceof Blob) {
    url = URL.createObjectURL(url) // 创建blob地址
  }
  var aLink = document.createElement('a')
  aLink.href = url
  aLink.download = saveName || '' // HTML5新增的属性，指定保存文件名，可以不要后缀，注意，file:///模式下不会生效
  var event
  if (window.MouseEvent) event = new MouseEvent('click')
  else {
    event = document.createEvent('MouseEvents')
    event.initMouseEvent('click', true, false, window, 0, 0, 0, 0, 0, false, false, false, false, 0, null)
  }
  aLink.dispatchEvent(event)
}
